FUNK MUNK, I share your bewilderment about the hyphenated variations many Americans have adapted to help them feel comfortable saying, "He's Japanese....or He's Korean....or He's a black guy."
A lot of it likely stems not so much from P.C., but rather from the dismal knowledge of geography most Americans own.
Thus, "Asian-American" can mean "all slant-eyed people" because after all, "aren't all those countries pretty much the same?" to a guy who doesn't know whether a given U.S. state is west or east of the Mississippi.
Never forget a job I had Years Ago where we were doing data entry, building a Preferred Customer database for Hilton Corp.
About 20 of us, handling customer feedback cards from around the U.S. and around the world.
Thus each entry had Name, Address etc and the Address included a code for Country.
Girl a couple seats down, about 20 years old or so, asks out loud, "What's the country code for Hawaii?"
I stifled a laugh and simply replied, USA.
She's like, "Oh really?"
Me: Yeah, you know, like Pearl Harbor?"
Her: Huh?
Me: (In head) THANK YOU MOM AND DAD FOR MAKING SURE I PAID ATTENTION IN SCHOOL.